


Operational Mishaps

by JayTDawgzone9999



Category: Dr. STONE (Anime), Dr. STONE (Manga)
Genre: Belligerent Sexual Tension, F/M, Gratuitous Smut, Kohaku needs to use the shampoo Senku makes for her more often, Rough Sex, Smut, What-If, What-if Scenario, what-if fic
Language: English
Status: Completed
Published: 2019-12-20
Updated: 2019-12-20
Packaged: 2021-02-26 04:00:14
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,238
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21867133
Author URL: https://archiveofourown.org/users/JayTDawgzone9999/pseuds/JayTDawgzone9999
Summary: When Kohaku, Ginrou, and Amaryllis become a part of the master's harem, Kohaku literally runs into a surprise that leads to her having a very interesting night.
Relationships: Mozu (Dr. STONE)/Kohaku (Dr. STONE)
Kudos: 16





	Operational Mishaps

**Author's Note:**

> This is just a what-if scenario I cooked up to justify some extremely wrong and extremely horny smut. I don't even really know if I ship this or not but I feel like the two of them have just the right kind of awkward sexual tension to make for good fanfic material and everything snowballed from there.

Even before meeting Senku, Kohaku had sometimes wondered if people could travel to the stars that dotted the night sky. Perhaps living there might be more interesting or hold some new and exciting discoveries that could change the course of humankind's history. Perhaps there were other planets out there, places with other people who might be looking up at the night sky and wondering about the same things themselves. At any rate, it was enough to distract Kohaku until she reached the master's treehouse, hoping against hope that there was even the slightest chance the master might actually be a decent person. Doubtful, she realized, but how much could it hurt to hope anyways? 

"Noooo, don't go! What if you get killed? What if we get attacked?! Don't leave me Kohaku!" Ginrou wailed, clutching her dress in desperation with tears streaming down his face as the three of them walked along the bridge. 

"You know I don't have a choice, I was the one summoned to see the master after all." Kohaku gently scolded Ginrou, removing his hands from her dress. 

She knew he was too scared to be thinking about anything sexual at the moment so when he gripped onto her harder, sniffling and crying, Kohaku didn't yell at him or slap him, instead gently grabbing his hands and reassuring him that not only would she be okay but she would make sure that nobody hurt him or Amaryllis. 

"Don't worry, Ginrou, Kohaku's really strong, I'm sure she'll be fine." Amaryllis added, trying her best to help Kohaku calm him down before they had to leave her to make the rest of the trip by herself. 

"I'll be back sooner than you think, just you wait." Kohaku told them both. "And besides, once we get information about the master, we'll have the upper hand. It'll all work out. Kohaku added when they reached the point where they had to separate. 

"If you don't come back....I'll....I'll do something! I promise! You better come back soon!" Ginrou yelled to Kohaku as she walked off. 

"You'll see, believe me, I'll be back before you even know it!" Kohaku said, waving to both her friends before disappearing out of their sight. 

Not too far above them, a certain warrior was sitting in a tree, observing the scene that unfolded below him with nothing more than a hint of amusement on his otherwise emotionless face. He never liked the old geezer and if by some random chance someone else managed to off the ugly bastard, well, he certainly wouldn't complain, and no doubt the girls in the harem would appreciate it as well.

____

When Kohaku reached the treehouse, she stayed still for a moment shifting her weight, still rather uncomfortable in the fancy dress that was tighter and more form-fitting than she was accustomed to. Oh well, wasn't like she'd have to wear it for more than a day or two if everything went according to plan. It was quiet, more than she expected, but then, she didn't know much about the master, maybe he liked it that way, she thought. 

"You called, master?" Kohaku heard an unpleasant sounding male voice murmur in the next room. "Ah, yes, so it'll be the usual, then? Very well." 

Upon closer inspection, the next room was not, in fact a room at all, just part of the room that was separated from the rest by a curtain, and when a certain old man walked out from behind the curtain, Kohaku steeled herself, using all her willpower to not take out her hidden knife and attack him right then and there. No doubt Ginrou would have screamed in terror if he saw him, but Kohaku wasn't Ginrou and all she could think about was how much she wanted to get this over with and how determined she was to do so at any cost.

"Now, there's nothing to be nervous about, but before you can spend time alone with the master, it's my responsibility to make sure you've been vetted." the creepy old man, who neglected to introduce himself, said. 

The sly grin on his face was nothing short of hideous but Kohaku refused to lose her cool that easily. She was here for one thing and one thing only-information. Senku and everyone else were depending on her and she would never be able to forgive herself if she let them down. 

"Vetted?" she asked, not understanding what the word meant. 

"In other words, before you will be permitted to spend time alone with the master, this old man will teach you how to satisfy a man first." 

Oh God, Kohaku thought, a sudden shiver of disgust shooting up her spine. She knew it was too early, but there was no way in hell she was going to let this loathsome creature lay a hand on her. Some things were simply too unbearable to endure, she thought, looking up at him with the fakest doe eyed smile she could muster. 

"Well, if that's the case, then I'm prepared to do what it takes." she lied, stepping on part of the floor that she realized made a creaking sound in the hopes that the noise might catch his attention for just long enough. 

While the old man, who had yet to give her his name, approached her, he paused for a moment, wanting to take his time to look her over and appreciate the sight. 

Unfortunately for Koahku, there was precious little in the room that could serve as a possible distraction so she supposed she would have to make one, she thought, purposely taking a step forward and tripping, landing flat on her ass. 

"Oh, I'm terribly sorry, I can be a bit clumsy sometimes." she apologized in the fakest voice she had ever used, using the moment he was distracted by the sound to take Senku's special pineapple bomb out. 

___

Kohaku's heart was pounding in her chest harder than ever before when, after the old man had passed out, she ventured to take a look behind the curtain and found a horribly disfigured, decayed stone statue. 

"Holy shit." 

Her thoughts were nothing but a jumbled mess when she darted out of the treehouse, not wasting a moment, as she wasn't about to risk losing the precious time the bomb afforded her to make her escape. More than anything else, it was absolutely essential that she tell everyone about the statue as soon as possible, she told herself as she ran back the way she came, as fast as her legs would carry her, taking off her shoes and tossing them off the side of the bridge to allow herself to run even faster. 

Had Ginrou been in her place, she thought, there was no way he'd have been able to run away before the old man woke up, but thanks to her lifetime of training and carrying those heavy pots of water for Ruri, Kohaku could run much faster than a normal person and she made it all the way back to the point where she had to separate from Ginrou and Amaryllis before crashing into a very literal obstacle that blocked her path. 

Upon making contact with the obstacle, she realized the surface she had landed on felt much too warm-mainly because the surface she landed on wasn't a what but a who, she realized in shock when she saw a familiar face looking up at her, flashing a smirk at her before she realized one of his hands was resting on her back. 

"Oh fuck....." Kohaku's mouth opened but words refused to come out, gritting her teeth after her moment of shock when she realized who she was looking at (and looking back at her.)

"Well, this is an interesting surprise." Mozu commented, his hand snaking dangerously lower, giving her ass a squeeze before she pushed herself off him, her face flushed with embarrassment and anger. "You and your friends are the invaders, aren't you?" he continued, the odd calmness of his voice at odds with what he said. "You know you can't deny it, I heard you all earlier, so why don't you go on and tell me where they are?" he replied, grabbing his spear and getting into a suitable fighting stance before she could stop him. 

"Oh, and what makes you think I would do that? You think I'd give up my allies that easily?" 

Mozu looked her over, the expression on his face revealing no signs of frustration or anger. "Probably not, but I figured I'd give it a try." he replied in the same relaxed, unbothered tone of voice as before. "But you know, if you let me in on that secret, maybe we can work something out. Who knows, maybe nobody will have to die." 

"If you mean you'll leave me alone and not do anything to hurt them, then maybe, but why should I trust you to keep your word?" 

Kohaku couldn't help but notice that he seemed less concerned than he should be, part of her wondered if that was due to his strength-as much as she hated to admit it, she realized he was probably stronger than her and by quite a lot too-he could kill her with one blow if need be, she acknowledged. If the way he held the giant spear in his right hand was any indication, he was likely the strongest man on the island, the thought doing nothing to comfort her at all. Still, given the choice between fighting Mozu and having to have sex with the creepy old man, Kohaku would definitely choose the first over the second, so she took her knife out, glaring Mozu down with an eager expression. If he wanted a fight, he would get one alright, she told herself. 

Of course, bad luck had to give Kohaku yet another visit when a bunch of warriors ran towards her, shouting and screaming with weapons in hand. 

"There she is, I bet she's one of the invaders, kill her!" one of them shouted before Mozu made short work of them with a single swing of his spear. 

"Kill? Who said you could kill her?" Mozu yelled. 

"But-" a weak voice said.

"Shut up." Mozu snapped, terrifying the beaten warrior further into submission. "Killing her would be a waste of beauty, and even if she was ugly, this is my fight so you have no right to interfere." 

"Wow, he's a real piece of work...." Kohaku thought, torn on whether she should be grateful or not. 

Did he save her from what might have turned out to be an unpleasant fate? Arguably yes. Was he also easy on the eyes? Very much so. Very, very easy on the eyes, she thought, hating herself for every second it took for the thought to pass through her mind. Was he also an unstable jackass who had an ego as monstrous as his strength? Absolutely. 

What a night this was becoming, Kohaku thought, reminding herself that whatever the case, it was still better than having to be stuck in the tree-house with the creepy old man and the decayed statue that used to be the real master.

"Hm, well, now that that's been deal with, there's an endless list of possibilities just waiting to be considered, aren't there?" Mozu remarked after both of them noted that all the other warriors had been knocked out. "Who knows what could happen?" 

"I know which one I'm interested in." Kohaku remarked, rushing towards him to attack him. "The one where I kick your ass." 

Though the kick she delivered was nothing short of excellent both in form and the level of power behind it, Mozu blocked it effortlessly. "You're pretty strong." he said, eyeing her with a bit more interest than she could justify by her attacking him. "So you should be able to figure out that there's no way you'll be able to beat me." 

"And you expect me to give up that easily? You're out of your mind." Kohaku shot back, rushing to attack him again, this time using her knife. "I haven't survived as long as I have by getting my ass kicked by guys like you." 

Mozu grinned, holding his spear out to block her next attack. "Maybe, but why don't we just get right to it and get friendly with each other? You'll love it so much you'll be dying to spill everything." 

"Your ego is worse than your lack of impulse control." Kohaku replied, getting back up after he knocked her down by blocking her attack with his spear, attacking him a third time and managing to hit him (even if it did nothing to actually hurt him.) What came out of her mouth next was a complete accident but thanks to her adrenaline running crazy for the last few hours and her emotions being all over the place, she was powerless to stop it. "Men who boast and can't back it up aren't my type at all." 

Mozu, never one to waste a good opportunity to exploit awkward belligerent sexual tension, wasted no time in pinning Kohaku to the nearest tree, eyeing her with a level of amusement roughly comparable to a kid in a candy store the size of Texas. Whatever was going through Kohaku's mind at the moment (and boy, was there a lot,) she couldn't even begin to convert any of it into coherent words. Mozu, of course, couldn't have cared less if someone paid him, which was all too obvious judging by the look on his face. 

"Is that so? Then how about you give me a chance to prove you wrong?" Mozu said, holding her face in his free hand and tilting her chin up towards him. 

Kohaku scoffed, grabbing his hand and removing it from her chin. "Has that ever worked on any other girls?" 

"Of course not, because none of them ever doubted that I'd be able to give them a good time." Mozu replied without missing a beat, pinning her hand above her head. "You know, I don't mind girls like you though. Just makes things more interesting." 

Kohaku's heart was slamming against her rib-cage and her chest felt tighter than drum, but she refused to turn into a stuttering, blushy mess around a man like him of all people. Compared to other men, his face and his body were more than pleasant enough to look at but everything else about him that wasn't visible to the naked eye needed a hell of a lot of work. 

"Just between you and me," he continued, lowering his voice to just above a whisper as he bent down, his face close to her ear. "I don't care what happens to the old geezer. You and your friends want to kill him, be my guest. I was planning on doing it myself, but if you let me show you a good time, I'll let you and your friends get first dibs, otherwise, you can fight me for it. 

Kohaku rolled around several conflicting trains of thought in her head at the same time, doing her best not to react when he squeezed her wrist a little harder as he moved in closer to her. If she let him kill the old man, it would be ten billion percent harder for Senku to get his hands on the petrification device and with a mission as risky as this, Kohaku couldn't afford to lead anything to chance. Of course Mozu was a jerk and not really her type, she told herself, if mostly just for her own mental comfort, even as certain familiar shivery little feelings crept up her spine when he eliminated the gap of space in between them by all but a millimeter. As much of a jerk as he was, though, Kohaku had no choice but to think things through logically, and logic dictated that she and her friends killing the old man would benefit them in the long run whereas Mozu killing him would only be a temporary help. It was just simple logic, right?

_____

Kohaku didn't even know who the tiny hut belonged to and after a moment or so, she decided she didn't care, noting with pleasant surprise that the bed Mozu had pinned her down on was surprisingly comfortable, more so than anything she ever lied down on back home. She knew damn well she wasn't going to get much, if any, sleep tonight, but what was one night of bad sleep among everything else, she told herself when Mozu snaked a hand up her dress, ripping off the wrap on her leg that she used to hold her knife while he kissed her. He was better at it than she expected, the kiss being almost tender in comparison to the way he held her wrists above her head and the way his hand roamed up her thigh until it dipped in between her legs, finding that one spot that was already wet, something she regarded with only the faintest amount of shame.

She made her bed and now she'd have to lie in it, metaphorically speaking in all but the most basic sense of the term-there was a bed and she was indeed lying on it, but it wasn't her bed and she knew she'd be doing a lot more than just lying in it. Oh well, anything to kill a corrupt, twisted old man and get a fancy device Senku needed to save the world she told herself as Mozu left little kisses all over her soft pale skin, leaving a few teasing nips here and there that drew nothing more than the faintest amount of blood while he fingered her at just the right pace, or close enough-after a while, she was far enough along that she wished he would hurry up a little more, but it felt far better than she anticipated she would be comfortable admitting to herself if her hormones had been raging any less than they were at that very moment. 

"Let me guess, all the other girls tell you that you're good at that." Kohaku breathed after she felt a familiar spark jolt through her and he finally let up. 

"That's not all, not even close." Mozu replied, because of course he would say something like that, Kohaku scolded herself when he responded. 

"If you thought that felt good, you'll enjoy this a lot more." he replied, not giving her a chance to respond before he bent down, grabbing both of her thighs as he dipped his head between her legs.

Oh. What an interesting thing to do, Kohaku thought, her lips forming a small o-shape before she let out a small gasp of surprise of the best kind when she realized what he was doing. Did men outsider her village do that to their wives or lovers, she thought, entirely unprepared for the new and unusual sensation of what Mozu was doing to her. It felt way, way too good, she wondered why it was even possible to feel so good, or at lest as much as she could wonder about anything in her current state. 

"Ah-that's-" Kohaku found it hard to think about anything at all, much less form words, but somehow she had to figure it out, she thought-it felt too good to just hope he would be nice enough to continue until the hot electric feeling gathering insider her reached its peak. "don't stop-" 

Perhaps she was hearing things, but Kohaku could have sworn she heard Mozu hum in approval, a deep, rumbling sound low in his throat, as he kept at it, grabbing his thick, carefully tied braids with both hands as he sucked on a certain part of her that was remarkably sensitive, more so than she even knew was possible, making no noise except for soft gasps and moans while his face was buried between her thighs. She wasn't sure why his hair was so thick or why it resisted loosening from the strange things he used to tie it together, but it felt nice in her hands in a different kind of way and she closed her eyes as a sudden rush of the most intense electric white-hot spark jolted her throughout every inch of her body, crying out in a small, high-pitched voice, her hands buried in his thick, oddly textured hair. 

There was, of course, no way she would ever live this down, Kohaku acknowledged, so when Mozu finally came up for air, she wordlessly untied her hair, tossing the string she used to hold it together before he pinned her to the bed again. 

"For once, you were right about something." Kohaku admitted, grabbing his free hand before he could grab one of her breasts so she could pull him down closer when he leaned in for a kiss. In hindsight, it was probably a poor decision on some level or another, but for once, practical things didn't bother her at all, she thought as she grabbed a chunk of his hair again. 

"It happens more than you would think." Mozu replied without a hint of shame. "But don't worry, there's still plenty of time left for me to prove you wrong again." he continued, grabbing her thigh as he pushed her leg away from the other one just enough so he could kneel in between them.

"In that case, stop running your mouth and show me that you mean it." Kohaku replied, making no move to resist when he positioned himself to push inside her at just the right angle, going slowly until he was all the way inside, or close enough to not make a difference. 

Besides a small gasp when he first thrust inside her, Kohaku didn't make too much noise at first, noting with a sense of gratefulness than the slight amount of pain she felt disappeared after a few seconds, around the same time he started moving his hips to thrust in and out. 

It didn't take long for Mozu to get into a rhythm that suggested he knew exactly what he was doing and exactly what Kohaku could tolerate, going as fast and hard as possible but not a bit more, throwing her legs over his shoulders a minute or two in. They weren't quite long enough to hang over his shoulders, her ankles just barely resting on either side of his neck, but Mozu had no complaints-tall, small, thin, curvy, girls were girls and as long as they had a cute face, they were all a treat that he enjoyed indulging in, and in fact, he noted that Kohaku being as strong as she was made this a whole lot easier than it sometimes was. Some girls were more fragile and thus required him to be a lot more gentle, but he didn't have to worry about any of that with Kohaku, he noted as he pounded her as hard as he wanted. 

Kohaku's face was flushed and aside from a few soft gaps and sighs, she found it ridiculously hard to make any sort of noise at all, utterly overwhelmed by the sheer force Mozu was capable of. Oh well, worse things could happen, she realized, considering she had been in very real danger of ending her night with a much worse man only a few hours ago. 

Without warning, Mozu picked her up, holding her by the waist with one hand and holding one of her legs right above her knee, and within a few second's time, Kohaku realized Mozu was no long thrusting into her but moving her instead-"woah, this is-this is weird-" Kohaku thought, her shock lasting only a moment before she was overwhelmed by how good it felt. 

Not missing a beat, Mozu kept up the same pace as before, moving her with an almost brutal intensity, fucking her with quick, impossibly deep thrusts that hit all the right spots inside her each time, causing her to see stars behind her eyes as he was quite literally fucking her on his cock. 

Some part of Kohaku's brain would most likely experience distress upon remembering all of this later, but in the moment, it was hard for Kohaku to even remember her own name, much less how or why she got in her current position (figuratively and literally,) in the first place. Right now, she just wanted it to not stop, and Mozu more than delivered, holding up in the stamina part well enough to get through the better part of the night, grabbing her here and there and handling her in all sorts of very interesting ways that, prior to that night, Kohaku wasn't even aware were possible. 

All things must come to an end, however, emotionally conflicting or otherwise, and when Mozu was done, Kohaku had at least 3 orgasms, a chunk of her hair missing, several teeth-shaped indents and bruises all over her neck, chest, and stomach, and a dull, aching pain in her hips that she realized would make it difficult to walk for at least half a day, if not longer. 

All in a day's work, Kohaku thought, telling herself to remember to hold Mozu to his promise and vowing to try to contact Ginrou and Amaryllis as soon as possible after she regained the ability to speak and her legs worked properly again. 

**Author's Note:**

> Fun fact, some of the sex positions were inspired by some fanart that I unfortunately lost the link to because sometimes inspiration really can come from anywhere.


End file.
